Numerical jet machine for the application of a coating onto a substrate

ABSTRACT

The invention concerns a contactless numerical printing machine for products of average fluidity, such as varnish, glue, and conducting or scratchable ink, onto a substrate of variable thickness and dimensions. The machine includes a special device for printing without contact by projection. The projected materials are materials of average fluidity or composed of large-dimension molecules. The process used includes an electro-acoustic device for control of the projection, and a multiplicity of projection nozzles, each controlled individually. 
     The machine also includes a production chain with different work stations, whose printing devices are controlled by a computer management system. The production chain allows printing with a certain precision in given zones located during the processing by an appropriate work station.

RELATED APPLICATIONS

The present application is a reissue of U.S. patent application Ser. No.11/423,761, filed Jun. 13, 2006, the disclosure of which is herebyincorporated by reference herein in its entirety.

RELATED APPLICATIONS

The present application is based on, and claims priority from, FRApplication Number 0505981, filed Jun. 14, 2005, the disclosure of whichis hereby incorporated by reference herein in its entirety.

BRIEF SUMMARY OF THE INVENTION

The invention concerns the area of printing without physical contactonto a substrate of which at least one face is in plastic, and moreparticularly a machine, independent from a printing system, whichallows, before or after the printing system, the application by jet of aproduct having a viscosity going up to 1000 centipoises, and describedas average to large, such as varnish, glue, conducting or scratchableink, onto a substrate of variable thickness and dimensions.

There already exist jet printing systems operating with inks whoseviscosity is low and of the order of ten or so centipoises.

The existing systems use different techniques to project a bubble of inkonto the medium. According to a first technique, the ink contained in anozzle is expelled by a pressure created by a gaseous bubble formed at aheating resistance which creates a chemical reaction by converting theink to the gaseous state. Another technique to create pressure is to usea piezo-electric component which curves inward under the effect of anelectric voltage, so as to reduce the volume of the ink reservoir. Adroplet of ink is thus expelled from the nozzle.

These systems are however limited to inks or products with a controlledfluidity and a low viscosity as well as molecules of very smalldimension. For example, it is not possible with the existing appliancesto apply, without contact with the medium, products such as varnish,scratchable ink, conducting ink or glue, in particular onto a plasticsubstrate or the plastic face of a substrate.

Up to the present, the application of such products onto substrates,possibly plastic or of which one face is plastic coated, has been doneby spreading and not by projection, which renders complex theapplication to only a portion of surface of the substrate.

In addition, there is a real need, in particular for customisationpurposes or to render documents hard to falsify, to be able to apply alayer of product easily onto a substrate, possibly with a plastic face,in a given zone, before or after printing of the substrate.

BACKGROUND OF THE INVENTION

The present invention therefore has as its objective to overcome one ormore of the drawbacks of previous designs by creating a machine that canbe used to apply, without contact, onto a portion of a substrate,products or inks of average fluidity, such as varnish, glue, conductingor scratchable ink, onto a substrate of variable thickness anddimensions.

This objective is attained using a numerical jet machine for a viscousmaterial, for the application of a coating onto a plastic face of asubstrate, including an input magazine and an output magazine, acomputer device to manage the operations on each of the work stations, adevice for moving the substrate between the different work stations, adevice for grasping and transferring the substrate from the inputmagazine to the movement device and from the movement device to theoutput magazine, wherein it includes at least:

-   -   a read station which reads and determines at least one position        of the substrate and/or of markers placed on the substrate,    -   an application station composed of at least a series of nozzles        arranged in a ramp, each nozzle being piloted separately by a        command device, and fed from a reservoir containing product with        medium or high viscosity to be projected onto the substrate        during a relative movement between the substrate and the        application station, to effect the application of the product in        a given zone of the substrate, with the nozzles being hollow        needles each made to vibrate by a piezoelectric actuator affixed        to a resonator formed by the assembly of the hollow needle, with        the excitation of the actuator in duration and power determining        the dimensions and the shape of the drop of material of medium        or high viscosity,    -   a drying station with an infra-red or heated air current or UV        drying oven,

with the control of the command device of the application stationaccording to the position of the substrate, to the read station and tothe drying station, and/or with the management of the informationreceived at the different work stations to coordinate the operations,being effected by the management computer device in accordance with anestablished programming file.

According to another particular feature, the zone of application isspecified for each substrate by a configuration file concerning theshape of the zone, its position on the substrate in relation to thesubstrate markers, the quantity of product to be projected, a machinecontrol program making use of this information in order to translate itinto parameters of relative movement of the substrate and of thenozzles, for selective control of the nozzles and of reiteration ofoffset passage of the substrate in front of the nozzles to producejoined-up lines if necessary.

According to another particular feature, the ramp in which the nozzlesare arranged is equipped with a movement device in relation to themedium.

According to another particular feature, the projection site on thesubstrate is specified by the relative movement of the substrate inrelation to the ramp in which the nozzles are arranged.

According to another particular feature, the product is glue and thedrying is by heated air current.

According to another particular feature, the product is an aqueousvarnish and the drying is by infra-red.

According to another particular feature, the product is a scratchableopaque ink and the drying is by heated air current.

According to another particular feature, the machine includes a devicefor pressurizing the product to be projected.

Another objective is to propose the use of this machine in a system forthe preparation of identification documents (identity card, passport,driving license, etc.) or security documents (access badge, paymentcard, access key, etc.).

This objective is attained by the combination of a machine according tothe invention, used upstream or downstream of an independent printingstation or of a station for the installation of an electronic chip onthe substrate.

According to another particular feature, the machine according to theinvention is used upstream of the printing station for the applicationof glue in a zone other than that receiving the printing and a secondmachine is used downstream of the printing station for the applicationof a varnish on the printed part.

According to a variant, the machine is used upstream of the printingstation for the application of varnish in a zone other than the zonereceiving the printing and a second machine is used downstream of theprinting station for the application of glue in a third zone.

According to a variant, the machine is used upstream of the station forthe installation of an electronic chip on the substrate for theapplication of glue in the zone intended to receive the chip.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

The invention, its characteristics and its advantages will appear moreclearly on reading the description that follows with reference to thefigures listed below:

FIG. 1 represents an example of an automated device for printing ontomedia;

FIG. 2 represents an example of a projection device;

FIG. 3 represents examples of projection patterns on media;

FIG. 4 schematically represents a configuration for the use of twomachines according to the invention.

DETAILED DESCRIPTION

Let us first consider FIG. 1. The machine is controlled by a controlcomputer (10) which controls the different work stations, and also whichcollects the information from the different sensors. For example, thesensors give information on the positions of the substrates (13), on theconfiguration data of the substrates (13) or on the validationinformation following an operation, effected correctly or not. Thesubstrates (13) awaiting printing are placed in an input magazine (5)with a capacity specified according to the nature of the substrate (13)and of the printing needs. In one implementation example, the inputmagazine (5) is designed to accept several thousand substrates (13) ofvariable nature, of variable thickness up to 800 μm and of variabledimensions (credit-card format up to format AO) and possibly of which atleast one face is in plastic. Once the application process has ended,the substrates (13) are stored in an output magazine (8) with generallythe same capacity as the input magazine (5). A device for grasping (4)the substrates (13) is used to extract the substrates (13) from theinput magazine (5) and to place them on a conveyor in order to move themalong a working chain with several work stations. The first work stationof the chain is a margin stop (6) with indexing of the substrate (13)which allows positioning in relation to two reference edges or thedetection of a printed marker on the substrate (13). A sensor detectsthe position information and sends it to the computer by a cable orwireless network. This information, stored in memory in the computer,will then be reused by other work stations controlled by the computer.Checks are also performed in order to detect the presence of a substrate(13) unique to each station on the conveyor.

The next work station is the projection device (2, 9) for application ofthe product to the medium. The contactless projection device (2, 9) isdetailed in FIG. 2. The projection device includes a reservoir (9) whichcontains the viscous product to be projected. Non limiting examples ofproducts contained in the reservoir are varnish, scratchable ink,conducting ink or glue whose average viscosity is between 100 and 1000centipoises, that is much higher than the viscosity of printing inks,which are normally ten or so centipoises. The feeding of the reservoirnot shown is effected, for example, manually or automatically by a feedcircuit or indeed of semi-automatically by device controlled by anoperator. The reservoir (9) is connected to a pressurising device (10).In fact, the projection system requires a given pressure for correctoperation. The pressurising device therefore includes means to controland regulate the pressure of the product sent to the nozzles, and in anon limiting manner controlled by the computer. The nozzles fed directlyby the pressurising device (10) are all controlled individually by anozzle control device (11), in a non-limiting manner controlled by thecomputer. The nozzles are aligned and assembled on a ramp, thus forminga ramp of nozzles (12). Each nozzle is composed of the end of a hollowneedle which is made to vibrate by a piezoelectric actuator affixed tothe resonator formed by the assembly of the hollow needle on the ramp.The control of each nozzle is an electro-acoustical process, meaningthat the product is projected by a vibration controlled by electricexcitation. The nozzles spaced by 0.1 to 0.5 mm thus allow to cover aprecise surface.

The application zone is specified for each substrate by a configurationfile contained in a memory zone of the computer, concerning the shape ofthe zone, its position on the substrate in relation to the substratemarkers, the quantity of product to be projected, a machine controlprogram making use of this information in order to translate it intoparameters of relative movement of the substrate and of the nozzles,selective control of the nozzles and reiteration of the offset passageof the substrate in front of the nozzles to produce joined-up lines ifnecessary.

The next station of the projection machine is the drying oven (7). Theoven (7) is used to fully or partly dry the projected product. Thedrying, according to the applied product, can be performed by aninfra-red radiation in the case of an aqueous varnish or by a heatedair-current for glue or an scratchable ink or by UV, according to theprojected product. The drying then allows the substrate (13) to bestored in the output magazine (8), so that the projected product is nottransferred onto other substrates (13) or onto the magazine (8) withwhich the substrate (13) is in contact.

FIG. 3 gives non-limiting examples of applications effected byprojection onto substrates (13). Thus the application of a layer ofvarnish (14) is effected onto a face either before or after printing.For example, a layer of varnish occupies a zone on the substrate that ismore or less rectangular, and whose corners are rounded. In anon-limiting manner, a margin not covered with projected product is lefton the periphery of the face of the substrate. On a zone (16, FIG. 3) ofa substrate, a layer of thermally reactivable glue is placed in apattern, such as a small rectangle rounded at the corners. For exampledifferent patterns of scratchable ink (15) are applied to other zones,such as an arrow or a star for example, or any other pattern with, in anon-limiting manner, an outline formed of angles and straight or curvedlines.

With reference to FIG. 4, by the use of two machines, one (1A) beforethe printing, the other (1B) after printing, and loading the reservoirsof these machines with the appropriate viscous products, differentprintings are effected, in a non-limiting manner, on two faces of asubstrate. These printings can be zones that are printed and protectedby a varnish for example, zones printed and covered with an scratchableink or zones coated with glue or indeed a combination of these differentoptions on any face. Printing on the different faces is effected by aturning mechanism (not shown) between one machine and the next orprevious machine.

Electro-acoustic control is used to adjust the projection of material interms of duration and power. The application zones are then determinedby this numerical process with a precision of the order of 0.1 mm. Themachine can therefore apply a point or indeed can cover the wholesurface of a substrate. The application zone is specified for eachsubstrate by a configuration file concerning the shape of the zone, itsposition on the substrate in relation to the substrate markers, thequantity of product to be projected. A machine control program uses thisinformation in order to translate it into parameters of relativemovement of the substrate and of the nozzles, parameters for selectivecontrol of the nozzles and parameters for reiteration of the offsetpassage of the substrate in front of the nozzles to produce joined-uplines if necessary.

In another embodiment example, the working chain includes otheradditional work stations allowing, for example, the assembly ofdifferent parts together, in the case of application of glue to thespecified contact zones it should be obvious to people well-versed inthis area that this present invention allows methods of implementationin many other specific forms without moving outside the range ofapplication of the invention as claimed. As a consequence, the presentmethods of realisation should be seen as illustrations only, and can bemodified within the area specified by the scope of the attached claims,and the invention should not be limited to the details given above.

The invention claimed is:
 1. A numerical jet machine for viscousmaterial product for the application of a coating to a plastic face of asubstrate, including: a reservoir configured for including a viscousproduct having viscosity between 100 and 1000 centipoises, an inputmagazine and an output magazine, work stations and a computer device tomanage the operations on each of the work stations, a movement devicefor moving the substrate between the different work stations, a devicefor grasping and transferring the substrate from the input magazine tothe movement device and from the movement device to the output magazine,further comprising at leastsaid work stations comprising at least: aread station for reading and determining at least one position of thesubstrate and/or of markers placed on the substrate, aan applicationstation including a series of plural nozzles arranged in a ramp, each ofthe nozzles including a hollow needle, a piezoelectric actuator affixedto a resonator formed by an assembly included in each hollow needle, adrying station with an infra-red or heated air current of UV dryingoven; , wherein each hollow needle is piloted separately by a commandthe computer device, and is arranged to be fed from said reservoirconfigured for including said viscous product to be applied onto thesubstrate during relative movement between the substrate and theapplication station, to apply the product in a given zone on thesubstrate, wherein each hollow needle is arranged to be vibrated by itsassociated piezoelectric actuator, with the excitation of the actuator,in duration and power, determining the dimensions and the shape of thedrop of viscous product, to apply the product in a given applicationzone on the substrate, said application zone being defined for eachsubstrate by a configuration file concerning the zone shape, the zoneposition on the substrate in relation to the position determined by theread station, the quantity of product to be applied, wherein of themanagement computer device is arranged to be responsive to anestablished programming said configuration file for controlling thecommand device of the application station according to the positiontranslate the information into parameters of relative movement of thesubstrate, to the read station and to the drying station with themanagement of the nozzles, and selective control of the informationreceived at the different work stations to coordinate the operationseach actuator of each nozzle.
 2. A machine according to claim 1, whereinthe application zone is specified for each substrate by a configurationfile concerning the shape of the zone, the position of the zone on thesubstrate in relation to the substrate markers position determined bythe read station, the quantity of product to be applied, with a machinecontrol program arranged to use this information for translating theinformation into parameters of relative movement of the substrate and ofthe nozzles, for selective control of the nozzles and for reiteration ofthe offset passage of the substrate in front of the nozzles to producejoined-up lines if necessary.
 3. A machine according to claim 1, whereinthe ramp in which the nozzles are arranged is equipped with a movementresource in relation to the medium the substrate defining said relativemovement between the substrate and the application station.
 4. A machineaccording to one of claim 1, wherein the said application site zone onthe substrate is specified by the relative movement of the substrate inrelation to the ramp on which the nozzles are arranged.
 5. A machineaccording to one of claim 1, wherein the product is glue and the dryingstation includes a heated air current source.
 6. The machine accordingto claim 5 in combination with an independent printing station or of astation for installing an electronic chip on the substrate, wherein themachine is disposed upstream or downstream of the independent printingstation or of a station for installing an electronic chip on thesubstrate.
 7. The combination according to claim 6, wherein the a firstmachine is disposed upstream of the printing station, for applying gluein a zone other than the zone receiving the printing, and the a secondmachine is disposed downstream of the printing station for applyingvarnish on the printed part.
 8. The combination according to claim 6,wherein the a second machine is disposed upstream of the printingstation for applying varnish in a zone other than the zone receiving theprinting, and the a first machine is disposed downstream of the printingstation for applying glue in a third zone.
 9. The combination accordingto claim 6, wherein the a first machine is disposed upstream of thestation for the installation of an electronic chip on the substrateapplying glue in the zone intended to receive the chip.
 10. A machineaccording to one of claim 1, wherein the product is an aqueous varnishand the drying station includes an infra-red source.
 11. The machineaccording to claim 10 in combination with an independent printingstation or of a station for installing an electronic chip on thesubstrate, wherein the machine is disposed upstream or downstream of theindependent printing station or of a station for installing anelectronic chip on the substrate.
 12. A machine according to one ofclaim 1, wherein the product is a scratchable opaque ink and the dryingstation includes a heated air current source.
 13. A machine according toone of claim 1, further comprising a device for pressuring the productto be applied.
 14. A machine according to claim 5, wherein the workstations further comprise an additional station for assembling differentparts together, in the case of application of glue to contact zones. 15.A machine according to claim 1, wherein the substrate is paper with anaqueous ink printed thereon prior to application of viscous product. 16.A numerical jet machine for the application of a viscous product on asubstrate, comprising: a reservoir configured for including a viscousproduct having viscosity between 100 and 1000 centipoises; an inputmagazine and an output magazine; one or more work stations and acomputer device to manage the operations on each of the work stations; amovement device for moving the substrate between the work stations; adevice for grasping and transferring the substrate from the inputmagazine to the movement device and from the movement device to theoutput magazine; said one or more work stations including: a readstation for reading and determining at least one position of thesubstrate and/or of markers placed on the substrate; a drying station;and an application station comprising a series of nozzles arranged in aramp, each nozzle being: separately controllable by the computer device,actuable by a piezoelectric actuator, and arranged to be fed from thereservoir configured for including said viscous product to be appliedonto the substrate during relative movement between the substrate andthe application station, to apply the product in a given applicationzone on the substrate, said computer device managing the operations oneach of the work stations according to the position of the substrate, tothe read station and to the drying station, and/or with the managementof the information received at the different work stations to coordinatethe operations; and said application zone being defined for eachsubstrate by a configuration file concerning the zone shape, the zoneposition on the substrate in relation to the position determined by theread station, the quantity of product to be applied, the computer devicearranged to be responsive to the configuration file to translate theinformation into parameters of relative movement of the substrate and ofthe nozzles, and selective control of each actuator of each nozzle. 17.A machine according to claim 16, wherein the computer device is arrangedto control a reiterated driving of the same substrate in front of thenozzles to produce jointed lines.
 18. A machine according to claim 16,wherein the computer device is arranged to control the excitation of theactuator, in duration and power, to determine the dimensions and theshape of a viscous product drop in accordance with an average viscosityof the product.
 19. A machine according to claim 16, wherein the ramp isprovided with a movement device in relation to the substrate definingsaid relative movement between the substrate and the applicationstation.
 20. A machine according to claim 16, wherein the applicationzone on the substrate is defined by the relative movement of thesubstrate in relation to the ramp.
 21. A machine according to claim 16,wherein the viscous product is a glue and the drying station comprises aheated air source.
 22. The machine according to claim 21 in combinationwith an independent printing station or of a station for installing anelectronic chip on the substrate, one or more of the machines disposedupstream or downstream of the independent printing station or of astation for installing an electronic chip on the substrate.
 23. Thecombination according to claim 22, further comprising a first machine,using a glue as viscous product and disposed upstream of the independentprinting station, for applying glue in a zone other than a printing zonereceiving the printing, and a second machine using a varnish disposeddownstream of the printing station for applying varnish on the printingzone.
 24. The combination according to claim 22, further comprising asecond machine, using a varnish as viscous product and disposed upstreamof the independent printing station for applying varnish in a zone otherthan a printing zone receiving the printing, and a first machinedisposed downstream of the printing station for applying glue in a thirdzone.
 25. The combination according to claim 22, further comprising afirst machine, using a glue as viscous product and disposed upstream ofthe station for the installation of an electronic chip on the substrateapplying glue in the zone which is to receive the chip.
 26. Thecombination according to claim 22, the machine disposed downstream ofthe printing station for applying varnish on a printed portion of thesubstrate, further comprising a second machine using varnish as viscousproduct arranged upstream of the printing station for applying varnishin a zone other than a printing zone receiving the printing.
 27. Thecombination according to claim 22, wherein the device for grasping andtransferring is adapted for a plastic substrate and the viscous productis adapted for a plastic substrate.
 28. A machine according to claim 21,wherein the work stations further comprise an additional station forassembling different parts together, in the case of application of glueto contact zones.
 29. A machine according to claim 16, wherein theviscous product is an aqueous varnish and the drying station comprisesan infra red source.
 30. A machine according to claim 16, wherein theviscous product is a scratchable opaque ink and the drying stationcomprises a heated air flow source.
 31. A machine according to claim 16,comprising a device pressuring the viscous product to be applied.
 32. Anumerical jet machine for the application of a coating of varnish on asubstrate, comprising: a reservoir including a varnish having viscositybetween 10 and 1000 centipoises; an input magazine and an outputmagazine; one or more work stations and a computer device to manage theoperations on each of the work stations; a movement device for movingthe substrate between the work stations; a device for grasping andtransferring the substrate from the input magazine to the movementdevice and from the movement device to the output magazine; said one ormore work stations comprising: a read station for reading anddetermining at least one position of the substrate and/or of markersplaced on the substrate; a drying station; and an application stationcomprising a series of nozzles arranged in a ramp; each nozzle being:separately controllable by the computer device, actuable by apiezoelectric actuator, and arranged to be fed from the reservoirincluding said viscous product to be applied onto the substrate duringrelative movement between the substrate and the application station, toapply the product in a given application zone on the substrate, saidcomputer device managing the operations on each of the work stationsaccording to the position of the substrate, to the read station and tothe drying station, and/or with the management of the informationreceived at the different work stations to coordinate the operations;and said application zone being defined for each substrate by aconfiguration file concerning the zone shape, the zone position on thesubstrate in relation to the position determined by the read station,the quantity of product to be applied, the computer device arranged tobe responsive to the configuration file to translate the informationinto parameters of relative movement of the substrate and of thenozzles, and selective control of each actuator of each nozzle.
 33. Anumerical jet machine as claimed in claim 32, wherein the reservoirincludes a varnish having viscosity between 100 and 1000 centipoises.34. A numerical jet machine as claimed in claim 32, wherein thereservoir includes a varnish having viscosity greater than 10 and lessthan or equal to 1000 centipoises.